Chair glide and method of making the same



CHAIR GLIDE AND METHOD OF MAKING THE SAME Original Filed April 5, 1923 INVENTOR ATroRNE,

Patented Sept. 30, 1924.-

UNITED STAT-ES TUCK MANUFACTURING COMPANY, TION OF CONNECTICUT.

PATENT OFFICE.

I WILLIAM RAEBURN, QF WATERBURY, CONNECTICUT, ASSIGNOR TO THE MATTA- OF WATERBURY, CONNECTICUT, A CORPORA- CHAIR GLIDE AND METHOD OF MAKING THE SAME.

Continuation of application Serial No. 629,574, filed April 3, 1,923. This application filed November 24,

To all whom it may concern:

Be it knownthat I, WILLIAM RAEBURN, a citizen of the United States, residing at Waterbury, county of New Haven, State of Connecticut, have invented certain new and useful Improvements in Chair Glides and Methods of Making the Same, of which the following is a full, clear,'and exact description.

My invention relates to improvements in chair glides and methods of making the same and has for its object to provide a new and improved chair glide having a prong for securing the glide to the chair. It further has for its object to provide a chair glide having a hardened contact surface and a permanently secured tough prong which is soft relative to the contact surface though sufficiently hard for driving purposes.

This application is a continuation of my application Serial No. "629,574 filed April 3, 1923.

Heretofore chair glides: have been made with integral prongs located at their periph cries and attempts have been made to produce satisfactory chair glides having central prongs. The chair glides with the central prongs have, however, heretofore been found to be unsatisfactory, for the reason that either the contact surfaces were soft, or the prongs were so brittle as to be easily broken. By my invention a chair glide having a central prong is produced in which the contact 51: :face is glass hard and in which the prong, while of driving hardness, is

softer than the contact surface, and so tough and tenacious as not to be liable to be broken either in driving or in use.

The following is a description of my invention and of a chair glide constructed and made in accordance therewith, reference being had to the accompanying drawings, in which,

Figure 1 is a bottom plan view of my improved chair glide;

Fig. 2 is a side elevation of the same; and

Fig. center of Fig. 1.

Referring more particularly to the drawings, 1 is a prong having a pointed end 2 and an enlargement 3, and e is a saucer-like 3 is a partial section through the.

Serial No. 676,676.

head secured to the prong 1 and providing the contact surface of the chair glide.

Inthe preferred form I make the prong and head of substantially the shapes shown.

The head is made of steel and when apand yet of driving hardness (bv which I means sufficiently hard so that a prong made therefrom can be driven into the bottom of a chair leg made of wood such as ordinarily used for such legs, such for instance as oak, birch, hickory and the like), and which will not melt and will not become hard or brittle so as to easily break when subjected to treatment such as is ordinarily employed for the hardening of steel. The metal which I prefer to use for securing these characteristics in a prong is Monel metal, a permanently tough metal, whose composition is approximately 67 parts nickel, 30 parts copper with usually 2 or 3 parts of iron. Monel metal I describe as permanently tough since it does not become brittle when subjected to heat treatment such as is used for hardening steel, and by the expression permanently tough I mean a metal having that characteristic.

The head of the glide is primarily made of soft steel and is formed from blanks into the shape shown, and secured to the prong in the ordinary manner by an automatic nail machine such as is in common use for male ing headed nails of the general form shown. This head is made of saucer-like form with its edge portion somewhat thinned and bentup sharply. Its edge proper is somewhat After the prong and head have been assembled'in the manner described I subject them to a heat treatment which will result in hardening the head and which will not materially afi'ect the prong.

A suitable treatment for securing these results consists in di ping the assembled parts into a bath conslsting of 75 per cent soda cyanide and per cent soda ash heated to a temperature of about 1600. -The glides are placed in baskets and dipped into the bath being left therein for say, twenty minutes, or long enough to bring the glides to a temperature of 1500". They are then removed and, when heated, plunged into water so as to be quickly cooled. This results in making the heads of the glides glass hard but does vnot harden the prong so as to-make it brittle. After they are taken out they are placed in a rolling barrel and finished so as to give the contact surfaces of the heads a bright luster.

As will be evident to those skilled in the art, my invention permits of various modi- 3 fications without departing from the spirit thereof or the scope of the appended claims.

lVhat'I claim is: y 1. A chair glide consisting of a saucershaped hardened steel head and a softer tough prong of driving hardness, said head having swaged portions embracing one end head having swaged portions embracing one end of said prong so as to hold the two parts permanently together, said saucer-shaped -head having a sharpened edge adapted to aid the prong in resisting sidewise thrust.

4. A chair glide comprising a saucersha d head of hardened steel and a prong of onel metal having one end embraced by swaged portions of said saucer-shaped head so as to hold the two parts permanently together.

5. A. chair glide comprising a saucershafied head of lass hard steel and a prong of onel metal aving one end embraced by swaged portions of said saucer-shaped head so as to hold the two parts permanently together.

6. The method of making chair glides and similar articles, which consists in forming a permanently tough heat-resisting metallic prong of driving hardness, swaging'portions of a soft steel head about the end of the prong so as to permanently secure the head thereto, and sub'ecting the parts thus assembled to a bar ening heat treatment so as to harden the steel head.

7. The method of making chair glides and similar articles, which consists in forming a prong of Monel metal, swaging ortions of a soft steel head about the end 0 the prong so as to permanently secure the head thereto,

and subjecting the parts thus assembled to to a hardening heat treatment so as to harden the steel head.

8. The method of making chair glides and similar articles, which consists in forniin a permanently tou h heat-resisting meta lic prong of driving ardness, swaging portions of a soft steel head about the end of the prong so as to permanently secure the head 

